Postpartum depression affects between 8 and 28 percent or new mothers, with up to 68 percent of new mothers experiencing some degree of depressive symptoms. New fathers also experience depression, especially if their partner is depressed, and postpartum depression is correlated with decreased marital satisfaction. Parent-infant interaction and attachment are major indicators of the quality of the infant?s nurturing environment. Postpartum depression has significant negative effects on mother-infant interaction and on child development. Little is known about how the infant is affected when a new father is depressed or when both parents are experiencing depressive symptoms. Also unknown is whether or not a non-depressed father may buffer the negative effects of a mother?s postpartum depression on the infant. Using a family systems framework, this study aims to explore the influences of maternal depressive symptoms, paternal depressive symptoms, quality of the couple relationship and parental dyad functioning on the parent-infant interaction and each parent?s attachment to the infant. A mixed-method triangulated design involving quantitative measures at 2 to 3 months postpartum, followed by in-depth qualitative interviews and quantitative measurements at 6 to 12 months with a purposive subset of study families will be used. Findings will be interpreted to increase understanding of how postpartum depressive symptoms impact the family, and a family systems model of postpartum depression will be generated. Knowledge gained from this study may be useful in developing nursing interventions that will promote optimal parent-infant relationships in the early postpartum months. This may be especially crucial to child development in families where early parenting is compromised by depression.